Sheet-metal pipe



. 11,693,623 J. D. SMITH SHEET METAL'PIPE ec. 4, H928.

Filed July 27, 1927 Patented Dec. 4.-, 1928.'.

f n r man sie Josnri-r nonnnnsmfrn, on sfr. Menys, ontrnnro, ois-Nenn, Assiettes, or oirnlnanr fro SHEET-METAL Pira( Application led July 27,

rllhe principal object .of the invention is to"provide a simple and ei'i'ective lock for the scamv oil a collapsibleshect metal pipe which will en'cctively' secure the joint against sepa- *"1 and which will not add materially to ltttiO the cost oit producing the pipe.

rlhe principal features ot the invention consists in providing a rectangular sheet ot metal with tivo parallel edges turned back to form tlangeaone oi' said edges being provided with narrow lug extensions which project beyond one of said flanges and are adapted to be bent back over the edge ot the other flange to lock the two 'tianges against sepa-V ration.

ln the drawings, Figure-1 is a perspective view ot a sheet metal pipe constructed in accordance with this invent-ion. Y

Figure 2 is an enlarged sectional detail ot the seam and locking means showing the same before being locked.

Figure 3 is a View similar to Figure 2 showing the manner in which the seam isl locked.

Figure e is a fragmentary elevational view of the interior ot the pipe slioivingthe edges prior to being connected together and shov ing` the disposition of one of the locking lugs.

Figure 5 is a iragmentary view on a reduced scale of one lof the meeting edges of the pipe showing the arrangement oi the locking lugs at eitherjend.'

in the manufacturing ot'sheet metal pipes it has been found desirable to provide the pipes with separable joints or seams.

Such pipes may be paclred into compact 'torni tor shipping-purposesand in setting up the pipes it isnccessary to provide some 'forni of loch to proven 'the separation ot the seam and various provisions have been made tor locking the seams to. 'ether.

'ihepresent invention is directed to a simple locking means 'for a pipe oi this type and in c 'og the invention into eiiiect the sheet ot inetai from which the pipe is made is :toi-ninu with lug extensions l which are bent back from the edge 2 ot the sheet in Hat overlapping relation.

These lug extensions are preferably arranged vone at each end of the sheet in order to render the same readily accessible for reasons to be described later.

The sheet is rolled into a substantially cylindrical Ytorni with the lugs l disposed on the inside thereof and is provided with the usual beads 3 Which partially encircle the leer.' sei-istitu 208,85.

I pipe' andterminate a short distance from the edgcsoi" the pipe.

The opposing edges of the pipe are their bent bach in' the usual manner as shown in FigureV 2 to'provide the mating flanges et ando.` j.- i

lt will be noted that the base portion of the lug extension l is incorporated in the 'flange 5 and the remaining tree end 6 thercoil projects freely therebeyond as shown in Figures 2 and i ot the drawings. A

vWhen it is desired to complete the pipe the ianges et and 5 are interineshed to provide a close joint throughout the length of the pipe and the joint is then securely iocled against separation by simply bending the tree extending portion 6 oi' the lug` l back over the opposed portion of the iiange i as shown in Figure 3 of the drawings.

A very secure lock is thus obtained and it will be impossible for the joint, when thus secured,` to become accidentally separated and the locking means, being positioned adj acont the ends ot' the pipe, will be readily accessible for locking purposes.

`The present invention is particularly ap plicable for use with stove pipes but may be employed equally successfully on numerous forms or sizes ot sheet metal pipes without departing from the spirit of the invention as set forth.

`What l claim as my invention is l. in a sheet metal pipe, a sheet of metal bent into cylindrical form and provided with seam forming edges, and having portions of the body ot said sheet continuing beyond one of said edges and forming free integral lug extensions bent back over the other edge to secure the joint against separation.

2. ln a sheet incr-al pipe, la sheet oi' metal bent into cylindrical form and having portions of the body thereof continuing beyond one edge and forming lug extensions integral therewith, the latter being turned backwardly from one edge thereof to overlap the adjacent body portion, the meeting edges of the pipe being Aiianged longitudinally to form a seam, said lug extensions extending freelybeyond the flange formation and bent over one or the flanged meeting edges to lock the joint against separation.

3. In a sheet metal pipe, a sheet of metal bent into cylindrical form and having the meeting edges thereof flanged baolivardly to enga-ge each other in a longitudinal joint,

said sheet having portions of the body continuing beyond one of said edges and bent beckwardly therefrom und incorporated in the flange and forming lugs extending beh yond the flange edge bent over the opposite flanged edge to engage the saine to prevent the separation of the joint.

4E. A lool; Afor the senin of sheet inetnl pipes.)n Comprising the Combination with the seemed meeting edges, oi lng extensions formed by integral cont-intuitions of the body portion of .said sheet beyond one of said ineeting edges the latter being` turned inwardly and extending beyond the seemed edge and bent over the other seemed edge to secure the joint.

In zt sheet inetai pipe, a .sheet of nietal bent into cylindrical form and having one edge flanged outwardly and baekwardly, Said sheet having portions of the body extending beyond the other edge in tbe form of lugs,tlie lutter being bent backwardly in close overlapping Contact with tbe inner Wall of the pipo7 seid )letter edge being 'flanged inwardly and buekwzirdly the opposing portion o said lugs tontorining to the inner Wall of said flange the remaining-portion of said lugs being` iire and bent 'forwardly and embracing the tiret mentioned flange to prevent its dis- Y engagement from the latter lange.

JOS. DONALD SMTH. 

